<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_InfoCard
 * @subpackage Zend_InfoCard_Xml
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Exception.php 2794 2007-01-16 01:29:51Z bkarwin $
 * @author     John Coggeshall <john@zend.com>
 */

/**
 * Zend_InfoCard_Xml_Exception
 */
require_once 'Zend/InfoCard/Xml/Exception.php';

/**
 * Zend_InfoCard_Xml_Element_Interface
 */
require_once 'Zend/InfoCard/Xml/Element/Interface.php';

/**
 * Zend_Loader
 */
require_once 'Zend/Loader.php';

/**
 * An abstract class representing a an XML data block
 * 
 * @category   Zend
 * @package    Zend_InfoCard
 * @subpackage Zend_InfoCard_Xml
 * @copyright  Copyright (c) 2005-2007 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @author     John Coggeshall <john@zend.com>
 */
abstract class Zend_InfoCard_Xml_Element 
    extends SimpleXMLElement 
    implements Zend_InfoCard_Xml_Element_Interface 
{
	/**
	 * Convert the object to a string by displaying its XML content
	 *
	 * @return string an XML representation of the object
	 */
	public function __toString() 
    {
		return $this->asXML();
	}

	/**
	 * Converts an XML Element object into a DOM object 
	 *
	 * @throws Zend_InfoCard_Xml_Exception
	 * @param Zend_InfoCard_Xml_Element $e The object to convert
	 * @return DOMElement A DOMElement representation of the same object
	 */
	static public function convertToDOM(Zend_InfoCard_Xml_Element $e) 
    {
		$dom = dom_import_simplexml($e);
		
		if(!($dom instanceof DOMElement)) {
			// Zend_InfoCard_Xml_Element exntes SimpleXMLElement, so this should *never* fail
			// @codeCoverageIgnoreStart
			throw new Zend_InfoCard_Xml_Exception("Failed to convert between SimpleXML and DOM");
			// @codeCoverageIgnoreEnd
		}
		
		return $dom;
	}
	
	/**
	 * Converts a DOMElement object into the specific class
	 *
	 * @throws Zend_InfoCard_Xml_Exception
	 * @param DOMElement $e The DOMElement object to convert
	 * @param string $classname The name of the class to convert it to (must inhert from Zend_InfoCard_Xml_Element)
	 * @return Zend_InfoCard_Xml_Element a Xml Element object from the DOM element
	 */
	static public function convertToObject(DOMElement $e, $classname) 
    {
		
		Zend_Loader::loadClass($classname);
		
		$reflection = new ReflectionClass($classname);
		
		if(!$reflection->isSubclassOf('Zend_InfoCard_Xml_Element')) {
			throw new Zend_InfoCard_Xml_Exception("DOM element must be converted to an instance of Zend_InfoCard_Xml_Element");
		}
		
		$sxe = simplexml_import_dom($e, $classname); 
		
		if(!($sxe instanceof Zend_InfoCard_Xml_Element)) {
			// Since we just checked to see if this was a subclass of Zend_infoCard_Xml_Element this shoudl never fail
			// @codeCoverageIgnoreStart
			throw new Zend_InfoCard_Xml_Exception("Failed to convert between DOM and SimpleXML");
			// @codeCoverageIgnoreEnd
		}
		
		return $sxe;
	}
}
